The present invention relates to a liquid display device which uses a piston pump assembly to reciprocate two or more kinds of liquids of different colors and different specific gravities in changing the transparency of a transparent display board so as to regulate the light passing through.
A variety of aluminum windows are widely used in buildings for admission of light. In order to blocking or regulating the light, a curtain or a venetian blind or the like may be used. However, attaching a curtain or venetian blind or the like to a window for regulating the light may destroy the sense of beauty of the building and occupy much installation space. When a curtain or a venetian blind is used, it must be regularly washed so as to keep clean. Furthermore, because regular curtains and venetian blinds are commonly made of inflammable substances, they promote the development of a fire when it broke out.